樂天, 楽天, 乐天 or 낙천, meaning "optimism", may refer to:
Bai Juyi, courtesy name Letian (樂天), Chinese musician, poet, and politician during the Tang dynasty Jungjong of Joseon, courtesy name Nakcheon (낙천, 樂天), ruler of the Joseon dynasty of Korea Optimism (樂天), 2001 album by Hong Kong singer Louis Koo Rakuten (楽天), Japanese technology conglomerate
See also
Optimism (disambiguation)